okmijn

I'm a newbie to this site and this is my first post.

I've recently experienced a rattling(vibration)/growling noise around the engine when the car is running with the AC on. The sound gets louder when I put the car in drive and it goes away when I turn the AC off. The sound seems to be coming from underneath or next to the engine(right of engine when sitting in the car/left of engine when standing over the hood facing the engine)

Has anyone else experienced this? if so, how did you go about it?

I took it to Lexus and they told me its likely the water pump. The car drives great and I'm not noticing any leaks(water or otherwise) underneath the car.

I had to park the car for 6 weeks while on a military exercise, and dont recall hearing the noise before going away. could 6 weeks of inactivity on the engine have anything to do with this?

Any help is appreciated,

nevernu

what year, milage?

oldgrump

Because the noise disappears when you turn the AC "off" (the AC compressor is declutched and is not being driven by the engine) it is very possible that the noise is being generated by the AC compressor, or possibly the AC compressor drive pulley bearing. The drive pulley and the bearing will be rotating any time the engine is running, but with the AC compressor declutched there is no real load on the pulley (and the bearing), and the bearing is simply freewheeling and may not generate the noise. When the AC is "on" are you getting "cold" air from the system?

okmijn

Its a 2007 with 94k miles (151k Km)

The AC works great.

Today, with foot on the break I decided to shift into D with the AC on, and the noise was there again, as soon as I turned off the AC it went away. I also tried it in Reverse and same thing.

I had minor AC issues last year, a leak which I had a local shop repair, other than that, I've replaced 2x ignition coils and 2x O2 sensors. No other repairs other than wear and tear. I'm the second owner so dont know the full history prior to purchasing the car from Lexus over 2 years ago.

So should I shift away from the Waterpump and focus more on the AC compressor, or possibly the AC compressor drive pulley bearing?

Will I run the risk of causing more serious damage if I drove it for a bit?

Thank you again for taking the time to read my post.

oldgrump

Have you checked the coolant level lately? There can be a loss of coolant without it being noticed as drips under the car. There have been several instances of coolant leaking past the coolant pump shaft seal and contaminating the bearing on these cars.......so check the coolant level. You could also remove the serpentine belt which would allow you to check the compressor pulley bearing for excessive play/looseness and for being "rough" or noisy when spun by hand. Do the same for the coolant pump in particular and the belt tensioner pulley and the two idler pulleys. There is no guarantee that you'll find the source of the noise, but it's a starting point.
When it's making the noise does it "follow" the RPM or does it only occur at idle in D or R?

okmijn

Thanks oldgrump,

I dropped it off at the shop earlier and explained the problem to them. After checking the coolant, I noticed it needed topping up. I asked the technician to check the pulley/tensioner along with the AC compressor, pretty much everything you suggested as well as topping up the coolant.

I dont think the RPM affects the noise, at least not that I notice, but then again the engine noise could be blocking out the rattling/growling noise for all I know. what i do notice is that the more I drive and use the AC, the more noticeable the noise gets.

Well by the ed of today I should have a better idea of what the rattling noise is.

standby for updates,

okmijn

So apparently the source of the noise is my tensioner.
According to the mechanic its nothing to lose sleep over as it still appears to be working fine. I did end up replacing my serpentine belt (it was worn), the noise is still there but its not as loud, hoping the tension from the new belt will keep it that way.

I'm not ready to dish out close to a grand on a new tensioner+labour just yet since its not affecting anything else at the moment.

jonathan13

my car rattles from a pulley when the a/c is on only, i have diagnosed the problem and you can to with a few simple steps. step one go to auto part store and buy a stethoscope for automobile if you dont have one, sure u can a use pipe but its way more accurate with this tool. step 2 and 3 remove plastic trim from hood on passenger side area were water pump and belts is and remove, grab a jack and remove the driver side tire. step 3 under the tire u find 2 or 3 10 mm bolts hiding the belt area so remove. next make sure car is secure with jack stand parking brake and just be careful.( have someone help you tell them to put the emergency break on hold the brake do not let go and put the car in D while idling and foot on break to hear the noise more clear keep in mind the ac has to be on) make sure your stethoscope does not get stuck on any belts. step 4 carefully hover your stethoscope over the idle tension-er to hear sound note you do not have to put the stethoscope on top directly just hover over, next from the bottom very carefully hover you stethoscope over the water pump pulley. you should here the sound on both but it gets much louder when closer to water pump pulley! there fore the problem is the water pump because it is shot out it may not be leaking the rotating mechanism is damaged therefore needs to be replaced. now since you are already going to go into that area i recomend to switch the tensioner pulley if you can buy one say rock auto for 15$ or nearest autostore, autozone has is for 50. any ways replace the idle pulley just bcuz your there already and water pump. you can swap out thermostat but not nessary, oh yeah and might as well change the serpentine belt you will regret it if it rips later espicially if your not doing your own work, however if your problem is just the idle tensioner you are in luck and the job is so simple
good luck to us all

so if you dont want to read my description the problem is the water pump!
from mickyanic on youtube
i used a human stethpscope but it got really dirty and they might cost a little more

ChudiM

I am experiencing thesame noise more in D and R, when I shift to P it goes away once I turn off the AC it goes away, currently, when driving and in D when traffic stops I shift to N and it sort of goes away as well, generally when the engine is on load as the AC is on the noise is there. I will check out my tensioner as you have adviced.

Wilson2000

How many miles on your ES? If you are close to the mileage/years for a timing belt, you normally replace the tensioner, water pump, at the same time. $1,100 for the tensioner alone is too much! Find an independent shop that specializes in Toyota/Lexus and ask for quote for a package price.

ChudiM

Well , I got it used about 70k miles , and that same noise was there, took it to an independent shop and was told to do the water pump assy, changed out that with OEM spec. But the noise is still there and behaves as stated earlier. So am pretty much for the fact that it's a pulley gone bad, which is now the challenge. I have ordered a new serpentine belt for now pending when I get the quote for a new tensioner/labour

mrsteve7

The 2GR-FE engine has a timing chain, not a belt


The intake camshafts are driven by the crankshaft via the primary timing chain. The exhaust camshafts
are driven by the intake camshaft of the respective bank via the secondary timing chain.

Wilson2000

I'm not impressed with the shop that did your water pump if you had the same noise before the work as you did after the work. While they had your serpentine belt off, they should have checked all the components connected to the belt, i.e., tensioner pulley, any idling pulleys, the alternator, power steering pump, ac compressor and compressor clutch. As a poster wrote earlier, you could check these items yourself with an automotive stethoscope. I've also isolated noises like this with long screwdriver. You put the blade of the screwdriver on the component, and press your ear to the handle of the screwdriver. Or, cut off a piece of garden hose, or use any other sort of remnant hose you have on hand, and put one in your ear while moving the other end close to each component.

norakat

Did you ever resolve your problem?

I think I might have the same problem: rattling sound and tensioner vibrates when I turn the AC on.

I've been scouring the internet and looks like any number of things can cause this - anything that puts a load on the serpentine belt system including the alternator and water pump..

Its possible I have a low reading on the tension of the Serpentine belt with a kriket guage.

norakat

So did you resolve your problem?

I think I have the same problem. It sucks because apparently any number of things putting a load on the Serpentine belt system can cause this including your alternator.

One thing that can be done is go around feeling all the pulleys and see if you feel something.

Also you can check the tension on the belt.. only problem I keep getting different readings on my kricket guage.